This invention relates to new compositions of water-dispersed, carboxyl-containing reactive liquid polymers. Liquid polymers containing carboxyl groups are known in the art. For example, U.S. Pat. No. 3,285,949 describes carboxyl-terminated liquid polymers having a polymeric backbone comprising carbon-carbon linkages prepared by polymerizing dienes with or without vinyl nitriles in the presence of a bis-azocyanoacid initiator. Other carboxyl-containing liquid polymers having carbon-carbon linkage backbones and their uses are described in U.S. Pat. No. 4,119,592. Carboxyl-containing liquid polymers can also be prepared using the process described in U.S. Pat. No. 3,135,716 wherein monomers are polymerized using an organo-polyalkali metal compound to yield a polymer having a terminal alkali metal, and then post-reacting the polymer to form a terminal carboxyl group. The B.F. Goodrich Company markets a line of carboxyl-containing polymers containing carbon-carbon backbone linkages under the trademark Hycar.RTM. RLP.
Carboxyl-containing liquid polymers are useful as components in castable elastomeric systems, as tougheners for epoxy and polyester resins in structural plastics, and in paints, coatings, sealants, adhesives, and the like.
These carboxyl-containing liquid polymers have, heretofore, been used primarily in their liquid form or in the form of solvent solutions. However, in many applications such as in paints, coatings, sealants, and adhesives, it would be advantageous that the polymers be in the form of water-dispersion. A method that can be used to convert carboxyl-containing liquid polymers to water-dispersed compositions involves adding the polymer to a mixture of water and a high level of soap using a high speed mixer such as an Eppenbach homogenizer or a Minisonic homogenizer and agitating the mixture under high shear. Such processes require equipment and time to perform, introduce high levels of soap into the final composition, and have not resulted in completely satisfactory water-dispersed compositions.